Improved the Precision casting Silica sol shell process

As we all know ,There is a common global casting process silica sol shell have three disadvantages:
First, High cost
Second: Making shell cycle long time 
Third, Casting shelling poor.(High-strength shell residues)
According to statistics, Surface layer of refractory material shell common zircon sand, shell powder, 48% of raw material costs, 10% of total production costs (average) [1] .Scarcity of high quality zircon, Therefore find it substitutes or reduce their consumption of today's casting circles of common concern at home and abroad, one of the key research topics.
Gradually improve the "quick" promote the use of silica and vacuum drying equipment, Alleviate the shortcomings of the long cycle system shell.
Due to the high temperature strength silica shell (It is 6.7 times the sodium silicate), The corresponding residual strength is higher (2.8 times the Sodium silicate shell), thus Shelling performance far castings worse than sodium silicate. Combined with most of the production of precision castings are small pieces of the complex structure, High residual strength after shell treatment process will seriously affect productivity and hours worked increased material costs, reduce the casting surface quality, delays in delivery.
We learn the advanced experience from foreign counterparts, through many years hard study and practice, Achieved some success in reducing the silica shell production costs and improve the terms of shelling, Reached not only guarantee the product quality but also reduce production costs purpose.